Prostate cancer is one of the most common forms of cancer in men, and some of its traditional treatments can result in serious complications for the patient. Cryoablation is an emerging alternative that involves the controlled freezing of the prostate gland to destroy cancerous cells. In performing the procedure, the prostate is generally imaged and its size determined using an ultrasonic probe guided into the patient's rectum.
An aiming grid software program is typically activated and images of the prostate are projected on a screen. Under continuous monitoring with ultrasonic imaging, cryoablation probes are placed at predetermined sites within the prostate via the perineum using a “Cryo Grid,” which is a brachytherapy-like grid fixed to an ultrasound stepper. The placement of the cryoablation probes is such that cancerous sites are effectively ablated while sparing the non-diseased areas.
It is sometimes necessary to reposition the grid to ensure that the cryoablation probes reach their intended targets. Removing the grid is difficult because some cryoablation probes will already be in place and thus passing through the grid.